i've just switched my debian server from mod_php to fastcgi following this tutorial everything goes right but now i've found that one of the hosted application that using AMFPHP for flash remoting is broken. I'm trying to understand what's happend. Looking at it with FireBug and FireAMF it seems that the responses has a content but the Flash callbacks never get called and if i try to open the service browser it displays this error:

(mx.rpc::Fault)#0
errorID = 0
faultCode = "Client.Error.RequestTimeout"
faultDetail = "The request timeout for the sent message was reached without receiving a response from the server."
faultString = "Request timed out"
message = "faultCode:Client.Error.RequestTimeout faultString:'Request timed out' faultDetail:'The request timeout for the sent message was reached without receiving a response from the server.'"
name = "Error"
rootCause = (null)

It's strange it seems that the server takes a long time to responde, then (in the service browser) flash made a new call to the server and the old one get a response. Some problem with sessions ?